Double-acting reciprocating pump



Oct. 8, 1940. H. M- McNEW 2,217,287

DOUBLE-ACTING RECIPRQCATING PUMP Filed Feb. 20. r1939 Inventum HMMCNEW E E Q4@ /f/f/ Patented Oct. 8, 1940 UNITED STATES www1-norme nsclraooarme PUMP Henry M. McNew, Milwaukee, Wis., assigner of one-half to Michael Scarpace, Milwaukee, Wis.`

Application February zo, 1939, serial No. 251,342

2 Claims.

This invention appertains to pumps and compressors, and more particularly to an improved double-acting reciprocating pump for delivering a constant noninterrupted flow of fluid to its outlet on both strokes of its piston. y

One of the primary objects of my invention is to provide a double-acting reciprocating pump constructed in such a manner thatthe various parts thereof, such as pipes, joints, check valves,

etc., are formed from standard parts found in the open market, whereby the pump can be conveniently and economically kept in good running condition.

Another important object of my invention is to provide a novel means for guiding the pump or piston rod in the cylinder, whereby the same will not interfere with the intake or expulsion of fluid, the coupling for the intake and exhaust at one end of the cylinder forming said piston rod guide.

A further salient object of my invention is to provide a double-acting reciprocating pump of the above character, which will be durable and efficient in use, one that will be simple and easy to manufacture, and onel which can be placed upon the market at a reasonable cost.

With these and other objectsin view, the invention consists in the novel construction, arrangement, and formation of parts, as will be hereinafter more specifically described, claimed, and illustrated in the accompanying drawing, in which drawing:

The figure is a side elevational view of my improved pump, With parts -thereof broken away and in section to illustrate structural details.

Referring to the drawing in detail, the letter P generally indicates my improved pump, and the same may include a suitable base I formed from a casting or in any other desired way. The base I adjacent one end is provided with a support 2 on which is fitted the cylinder 3. The cylinder 3 could be formed from a length of pipe of the desired size and constructed from the preferred material, and, as shown, the ends of the cylinder 3 are fitted in annular grooves 4 in end cylinder heads 5 and 6. These cylinder heads are secured to the support 2 of the base I through the use of removable machine bolts 1. The heads 5 and 6 are also connected together by longitudinally extending bolts 8 disposed around the cylinder.

Reciprocally mounted in the cylinder is a piston 9 carrying suitable leather cups II and I2, which can be held thereon in any desired way. Rigidly secured to the axial center of the piston 9 is a piston or pump rod I3, which extends outwardly through the cylinder head 3 beyond the cylinder.

Obviously. the piston or pump rod I3 can be actuated in any preferred manner, and, as shown,

a hand operating lever I4 is provided. The lower end of the lever is rockably mounted upon a cross shaft I5 mounted in suitable bearings carried by the base I. 'I'he lever, at a point intermediate its ends, is-provided with slots I6 through which extend bearing pins I1 carried by the piston rod. The bearingpins can carry anti-friction rollers lo for engagement with the walls of the slots I3, if such should be preferred. An upright I8 can be formed on the base beyond the lever, and the upper end of this upright can have formed thereon a guide bearing I9 for the pump or piston rod u I3. Threaded into the cylinder head 51s a short length of pipe 20, which forms the inlet and exh-aust for fluid for one end f the cylinder. This short length of pipe 20 has threaded thereon a T-coupling 2l, and the opposite arms of the coupling have threaded therein pipe sections 22 and 23, which, in turn, carry check valves 24 and 25. Connected with the outer ends of the casings of the check valves 24 and 25 are short lengths of pipes 26 and 21, which carry elbow couplings 28 25 and 29, the purpose of which will be later set forth.

Threaded into the axial center of the cylinder head 6 is a short length of pipe 30 of va greater diameter than the pipe 20, and this pipe 30 has 30 threaded thereon a coupling 3l of a cruciform. The opposite arms of the coupling 3| have threaded therein reducing nipples 32 and 33, which receive short lengths of pipe 34 and 35, which, in turn, carry the check valves 36 and 31. 35 The outer ends of the casings of the cheek valves 36 and 31 have threaded therein short lengths of pipe 38 and 39, and these pipe lengths 38 and 39 carry T-couplings 40 and 4I. One arm of the coupling 40 is connected to the 40 elbow coupling 28 by a length of pipe 42. The T-coupling 4I is connected to the elbow coupling 29 by a length of pipe 43. If desired, the pipe lengths 42 and 43 can be formed in sections and connected together by turnbuckle pipe cou- 45 plings 44. T-he outer arm of the T-coupling 40 has connected thereto the outlet pipe 45, which leads to a suitable point of delivery. The outer arm of the T-coupling 4I has connected thereto the inlet pipe 46, which leads. to a suitable source 50 of liquid supply. v

Particular attention is invited to the fact that the piston or pump rod I3 extends through the relatively large pipe length 30 and the coupling 3|, as this forms an exceptionally simple iitting 55 and allows incumple and ernment guiding of the lpump rod Awithout interfering with the intake and exhausting of. iluid. 'I'he coupling 3l has its outer arm formed as a guide for the piston or' piston 'rod will not take up any active part of the cylinder, as thefcapacity of the cylinder adjacent the cylinder head 6 is slightly increased by said pipe length 30.

All of the check valves 24, 25, 36, and-31 open in the same direction. 'I'hus,the check valves 25 and 31 .open toward the cylinder, while `the check valves 24 and 36 open away' from-the cylinder.l Considering that the piston 9 is mov- .1

lng toward the right, then the piston will be creating a. suction within the. pipe 20. This suction will cause the closing. of the check' valve 24 and the opening of the check valve 25, and

the intaking of fluid' from the intake pipe 46. `25

Suction in the pipe 46 will hold the check valve 31 on its seat. Fluid in front of the piston will be forced out of the cylinder under pressure through the pipef30 and coupling 3l, and this pressure will also tend to hold the check valve 31 lon its seat, and will force open the check valve 3'6, and iluid will be delivered to the outlet pipe 45. 'I'his pressure will also tend to hold the check valve 24 on its seat.

. As the piston 9 moves toward the left, the uid will be expelled through the pipe 20 and the coupling 2l, and this pressure will hold the check valve 25 on itsseat and willmove the check valve 24 of! its seat, and liquid under pressure will ilow through the outlet pipe 45. This liquid under pressure willl also hold the valve' 36 on its seat. Movement of the piston. 9 to the left will cause a suction in the pipe 30, and this suction will also tend to hold the check valve 36 on its seat, and will lift the-check valve 31 on its seat, and liquid will beA drawn. into the right-hand end ofthe cylinder through the inlet pipe 46.

In order to prevent the striking of the leather cup I2 against the cylinder head 6, the piston or Pump' 48. Liquid-will readily ow through theap'ertures in the disc, and the disc is of such a thick-- rod I3 can loosely carry a perforated disc 4 ness as to act asa stop between the cylinder head 6 and the piston to prevent the contacting of the cup washer I2 with saidjcyllnder head 6.

Changes in details may be.made'without departing from the spirit or the scope of my invention, but -what I claim as new is:

1. A pump comprising, a base,` cylinder heads secured to the base, a cylinder-confined between'.

said heads, a pipe connected to one head, a pipe connected to the axial center of the other-head' having -a greater diameter thanthe rstmentioned pipe, couplings connected to said pipes, check valves communicating with the opposite arms of said couplings, an intake pipe on one side of. the cylinder communicating with certain check valves, and' an outlet pipe on the other side of the cylinder communicating Awith certain other of the check valves, a piston in said' cylinder, a piston rod connected'. tothe piston and extending through the pipe section of rela? ltively great diameter and the coupling. carried thereby, a packing -gland and guide for the piston rod carried by said last-mentioned coupling, a.

guide on the base arranged in spaced relation to the combined packing gland and guide for reoutlet pipe communicating .with the head, a 35 stufllng box on the outer end of the pipe, a piston reciprocally mounted in the cylinder, a piston rod secured t'o the piston and extending through the head, pipe, and stuillng box, valve-controlled inlet and outlet pipes communicating with the guide and mainliquidinlet and outlet pipe between the head andthe stuillng box, and a perforated buier disc loosely mounted on the piston'rod between the piston and the head to permit .the free ow of liquid therethrough, said4 HENRY M. MCNEW. 

